Fix gratipay team slug

gratipay/models/participant.py

@@ -1160,7 +1160,7 @@ def set_subscription_to(self, team, amount, update_self=True, update_team=True,
         if update_team:
             # Update receiving amount of team
             team.update_receiving(cursor)
-        if team.slug == 'Gratipay':
+        if team.slug == 'gratipay':
             # Update whether the subscriber is using Gratipay for free
             self.update_is_free_rider(None if amount == 0 else False, cursor)
 

tests/py/test_participant.py

@@ -499,7 +499,7 @@ def test_sst_is_free_rider_defaults_to_none(self):
 
     def test_sst_sets_is_free_rider_to_false(self):
         alice = self.make_participant('alice', claimed_time='now', last_bill_result='')
-        gratipay = self.make_team('Gratipay', owner=self.make_participant('Gratipay').username)
+        gratipay = self.make_team('gratipay', owner=self.make_participant('Gratipay').username)
         alice.set_subscription_to(gratipay, '0.01')
         assert alice.is_free_rider is False
         assert Participant.from_username('alice').is_free_rider is False